Return only CSV files from ftp server

Question

I have this working method which lists files from a ftp server, but I want to modify it to use it to download only csv files from the server. Here's the method:

private static void printFileDetails(FTPFile[] files) {
        DateFormat dateFormater = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        for (FTPFile file : files) {
            String details = file.getName();
            if (file.isDirectory()) {
                details = "[" + details + "]";
            }
            details += "\t\t" + file.getSize();
            details += "\t\t" + dateFormater.format(file.getTimestamp().getTime());

            System.out.println(details);
        }
    }

This is what I tried:

private static ArrayList<String[]> CsvFiles(FTPFile[] files)
            {
               // get list of files on given path
               for (FTPFile file : files) {
                String details = file.getName();
                //String[] CsvFiles;
                ArrayList<String> CsvFiles = new ArrayList<>();
                CsvFiles.add(details);


               }

                return CsvFiles[];
            }

At the return CsvFiles[]; netbeans is showing '.class' expected error, but that's not the only problem, I'm not even sure if the whole method is correct. Any help would be much appreciated.

Answer 1

we can use FTPFileFilter to filter files that we want to list

FTPFileFilter filter=new FTPFileFilter(){
        @Override
        public boolean accept(FTPFile ftpFile) {
            return (ftpFile.isFile() && ftpFile.getName().endsWith(".csv"));
        }
    };
FTPFile[] files=sessionForFtp.Files("directoryName", filter);

Answer 2

Do a details.endswith(".csv") on the file name.

(NOTE!! Un-tested code)

if(details.endsWith(".csv")) {
   CsvFiles.add(details);
}

With your code (and some clean up):

       private static ArrayList<String> CsvFiles(FTPFile[] files)
       {
           ArrayList<String> CsvFiles = new ArrayList<>();
           // get list of files on given path
           for (FTPFile file : files)
           {
              if(file.getName().endsWith(".csv")) {
                  CsvFiles.add(details);
              }
           }
           return CsvFiles;
        }

Answer 3

Your code looks like a puzzle.

1. I think you should declare to return ArrayList<String> instead of ArrayList<String[]> .
2. Declaration of the ArrayList must be outside the loop.
3. Try to avoid the same names for methods and for local variables.

Smth like this:

  private static ArrayList<String> getCsvFiles(FTPFile[] files){
      ArrayList<String> csvFiles = new ArrayList<>(); 
      for (FTPFile file : files) {
        String details = file.getName();
        //if file is csv
        csvFiles.add(details);
      }
      return csvFiles;
    }